> Just a block of cured epoxy resin isn't going to be tougher than glass. I wouldn't be so sure -- toughness has a specific meaning (energy before fracturing),

> Just a block of cured epoxy resin isn't going to be tougher than glass. I wouldn't be so sure -- toughness has a specific meaning (energy before fracturing), and polymers are generally going to be tougher than glass. http://www-materials.eng.cam.ac.uk/mpsite/interactive_charts/strength-toughness/basic.html http://www-materials.eng.cam.ac.uk/mpsite/interactive_charts... I haven't dug into it, but note how the article mixes up these terms to make it sound better: > transparent wood came out around three times stronger than transparent plastics like Plexiglass and about 10 times tougher than glass. If you plot that on those graphs it doesn't put it anywhere remarkable. edit: This is like trying to sell an electric bike by saying that it's three times faster than walking and 1/10 the price of a car -- ok, but how does it compare to a pedal bike? It's much more obvious when you do it with words that most people understand intuitively.